Peavey MediaMatrix X-Frame 88 Manual page 31

Topic Section
External DC Power Supply Interface
In most applications, the DC voltage would come directly from the X-Frame 88's CV ports. However, you can connect external
voltages to the X-Frame 88's control ports as well. This is handy when using external controllers that output precise variations
of voltage for control. In this case, you would have to connect the X-Frame 88's ground to the ground of the external voltage
source, and the positive DC voltage (0-10 V DC) from the external controller to the CV "IN" or return pin.
10V
POWER
OFF 10V
CV INPUTS CV INPUTS
WARNING: Do not exceed 10 volts DC when using an external power supply. Driving the V pin of the CV
input port with voltages exceeding 10 V DC could damage the X-Frame 88 and is not covered under warranty!
CV Input Notes....
In addition to the previous examples, the CV input ports provide even more options for external control of software devices. In
fact, the functionality of these ports and their associated software devices is limited only by the imagination of the system
designer.
Besides the switch, rotary control, and external voltage options shown in this manual, other common configurations include
opto-isolators, resistive voltage dividing networks, and TTL logic inputs.
Try to keep in mind that the CV input port is essentially an analog "portal" to a 256-step software device that resides inside of
the MediaMatrix® system. The voltages that you return to the port represent values within the software, that are converted to
actual control actions. These values are based on how many control positions are required, and how they are divided among
the 256 steps, or increments of 10 volts. For example, in a switching configuration, there are only two values, ON or OFF.
When the return pin sees 10 volts, an ON condition is present. How fine the range between ON and OFF is a matter of calibra-
tion.
When using third-party controllors to provide control voltage input, you should use controllers designed to output standard 0-
10 V DC control voltages for optimal performance.
In the case of variable controls, such as a fader that has a value of -100 dB to 0 dB, the range of the control voltage is calibrated
across 256 individual values that represent the audio range of the control. Exactly how much voltage that is required for the
control to adjust to exactly -12 dB, again, is a matter of calibration within the software.
For fixed position routers, the equation is even simpler. Since the port is simply distributing voltages across a common control,
a single multiple-position audio router requires only one port to operate its select switches. If the router has four inputs, the
voltage required to switch the inputs is based on a four-part division of 10 Volts. For an 8-input device, the division is eight,
and so on. The MediaMatrix software provides functionality to calibrate the external control, so that you can compensate for
wire distance, voltage loss, etc.
MediaMatrix - A Division Of Peavey Electronics Corp.
V1 10V V2
NO COM NC
V3 10V V4
NO COM NC
FAULT
CONTACT
SH
ARCHITECTURAL
ACOUSTICS
SH
RS-485
TX A
PC PORT
RS-232
RX A
PEAVEY ELECTRONICS CORP.
MERIDIAN, MS MADE IN U.S.A.
External Power Source
+DC (0-10V, Variable)
Ground
I/O EXPANSION
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